Method of blading rotors and other elements



R. C. ALLEN ET AL METHOD OF BLADING ROTORS AND OTHER ELEMENTS July 12, 1949.

Filed March 31, 1943 Patented July 12, 1949 METHOD OF BLADIN G ROTORS AND OTHER ELEMENTS Robert C. Allen and Cecil C. Jordan, Wls., asslgnors to Allis-Chalmers Milwaukee, Wis., a corporation ing Company, of Delaware Wauwatosa, Manufactur- Application March 31, 1943, Serial No. 481,206 3 Claims. Cl. 29-156.8)

This invention relates generally to the bladed elements of elastic fluid turbines, compressors and the like and more particularly to a method of and apparatus for assembling and attaching plain stamped, forged or rolled blade sections to the periphery of a rotor disk or other element to be] bladed.

The primary object of this invention is to provide an improved method of accurately blading rotors and other elements whereby manufacturing costs are materially reduced.

Another object of this invention is to provide an improved apparatus for use in carrying out the above specified method.

More specifically the method of'the present invention comprises providing an assembly having blades supported by concentrically spaced apertured base a d shroud strips through which the blades exten with their opposite ends terminating approximately flush with the inner and outer surfaces of such strips, positioning and holding the assembly 'Wlth the apertured portion of its base strip opposing a peripheral portion of an element to be bladed and with the outer ends of the blades and proximate outer surface portions of the shroud strip weldably exposed, welding substantially all of the ed by the inner ends of the blades and by the por-.

tion of the inner side of the base strip included between the inner ends of the blades to the op posed peripheral portion of the element, and welding the outer end of each blade to the outer contiguous portion of the shroud strip in a manher leaving exposed most all of the outer surface of the latter.

The invention accordingly consists of the various details of construction and of the correlations of steps and procedures constituting the method as hereinafter more fully set forth in the appended claims and in the detailed description, in which:

Fig.1 is a partial plan view illustrating the manner in which the blade elements are held in assembled relation against the periphery of a rotor disk;

Fig; 2 is a partial section taken on line II-II of Fig. 1;

Fig. 3 is a partial view similar to Fig. 2 illustrating the first steps performed in fusibly unit ing the blade elements to the various parts;

Fig. 4 illustrates the assembly in inverted poplain surface presentsition preparatory to completing the fusible union of said parts;

Fig. 5 iillustrates the complete fusible union of the various parts;

Fig. 6 is a partial plan view 01' the outer periphery of the united assembly shown in Fig. 5;

Fig. 7 is a view similar to moved;

Fig. 8 is a view of the outer periphery of the I one side thereof av circumferentiallyextending;

means of apparatus comprising;-

vembodying onone side thereof spaced inner and outer coaxial grooves 6 a coaxial disk huben- 7 projection 3 by I a circular jig member 4 and 1, respectively, and g Y gaging projection 8. adaptedto position said member on said disk with the inner surface of the Y groove 6 substantially flush with the outer surface on the projection 3; having on one side thereof spaced inner and outer coaxial grooves II and I? adapted for disposition I in spaced opposedlcoaxial relation to the grooves 6 and 'l in jig member 4; a plurality of clamping entially spaced peripheral portions of jig memher 4 by any suitablemeans such as tap bolts l4,

each member including an inwardly extending arm portion I6 carrying a tap bolt ll adapted to engage a mid-portion of jig member 8; a. tap

. bolt 18 or other equivalent means for detachably securing jig member 4 to the disk I; and shroud ring forming strips. or

a pair of base and 23, respectively; and

edges adapted for insertion inj'the opposed pairs bers 4 and 9 with their. apertures approximately flush with. the inner outer ends of the blades and mom ing device 26 operable to compress jection 3 on the disk I.

The apparatus just described can be readily" assembled by first inserting edge portions of the i9 and 2| in the grooves 6 base and shroud strips Fig. 5 illustrating the completed assembly with the excess material rean'annular jig memberv 9 l bands [Sand 2| having therein blade'receiving apertures'22 H having their opposite 1 and 1, respectively, in jig member 4 so that the apertures 22 and 23 in said strips are the insertion of blades therethrough, by next placing jig member 9 on said strips so that the edges of the strips are disposed within the grooves I I and I2, by next inserting the blades 24 through the alined apertures 22 and 23 to provide an assembly comprising said jig members, strips and blades in which the inner and outer ends of the blades are approximately flush with the inner and outer surfaces of the base and shroud strips, respectively, by next securing jig member 4 to the disk I by means of tap bolt I8 which together with the disk engaging projection 3 on member 4 positions said assembly on the disk I with the apertured portion of base strip I9 engaging and forming with the projection 3 on disk I an upwardly facing weld metal receiving groove 21, by next applying clamping ring 25 to the exposed outer ends of the blades 24 to thereby force the inner ends of the blades firmly against the projection 3 on disk I, and then securing clamping members I3 to jig member 4 and turning tap bolt I! to firmly hold the strips I9 and 2I between jig members 4 and 9 as shown.

Obviously, the assembly procedure just described can be readily varied if desired and all that is necessary in this connection is to position and hold apertured base and shroud ring forming strips in spaced concentric relation with their apertures alined for the insertion of blades therethrough, inserting blades through said alined apertures to provide an assembly in which the inner and outer ends of the blades are approximately flush with the inner and outer surfaces of the base and shroud strips, respectively, and positioning and holding the assembly thus formed with I the apertured portion of its base strip opposing a peripheral portion of an element to be bladed. The base and shroud bands may be formed with continuous ring strips, but a more accurate procedure is to employ band segments disposed in the end to end abutting ring forming relation indicated by the dotted line showing in Fig. 1 in which the ments are designated 28 and 29, respectively, since the length of the segments can be readily varied to eliminate accumulating errors in aperture spacing. Moreover, the widths of the base and shroud strips are preferably made equal and considerably greater than the width of the blades to be inserted therethrough in order to simplify the jig structure and in order to space the opposed surfaces of the jig members a suiiicient distance from the edges of the blades to facilitate fusibly uniting the apertured the opposed peripheral portion of the element to be bladed.

Upon completion of the assembly as shown in Fig. 2, the exposed apertured portion of the base strip, the exposed inner ends of the blades and exposed peripheral portion of disk I are fusibly united, preferably by substantially filling the groove 21 with weld metal; this operation being most easily performed with the assembly in the approximate position shown in Fig. 3. In addition, the exposed outer end portions of the blades may be fusibly united with proximate outer surface portions on the shroud strip by depositing weld metal on said portions as shown in Fig. 3, or if desired, weld metal can be readily deposited to fusibly unite both edge portions of the shroud strip to the proximate outer ends of the blades simply by placing the assembly shown in Fig. 3 in a vertical position, and this can be done base and shroud strip segalined for portion of the base strip to v either before or after weld metal has been deposited in the groove 21. After performing the hereinbefore specified operations, the jig members 4 and 3 and clamping ring 25 are removed from the now fusibly united assembly, and the projection 3 removed from the periphery of disk Iby a turning or other suitable operation to provide a second oppositely facing groove 3| exposing an apertured portion of the unnderside of the base strip and a portion of the inner ends of the blades 24. The assembly is then preferably positioned as shown in Fig. 4 and said groove filled with weld metal as shown in Fig. 5; the entire outer ends of the blades being fusibly united to the proximate outer surface portion of the shroud strip as shown either before or after depositing weld metal in the groove 3|.

A partial plan view of the assembly after all welding operations have been completed is shown in Fig. 6, and in this connection, particular attention is directed to the abutting ends of the shroud ring forming segments 29 which have their intermediate end portions spaced apart to provide transversely extending slots 32 separating the apertured portions of adjacent segments. All that remains to be done in order to complete the blading operation is to remove by turning or otherwise opposite edge portions of both strips, that is, of the base and shroud strips, to provide a shroud structure approximately equal in width tothe outer ends of the blades and a base structure approximately equal in width to the inner ends of the blades and to the peripheral portion of the disk I as shown in Fig. '7; sufficient material being removed from the edges of the shroud strip to expose the opposite ends of the slots 32, thereby forming gaps separating the end portions of adjacent segments as shown in Fig. 8. In other words, removing both edge portions of the shroud strip produces a shroud structure comprising circumferentially spaced segments each of which is integrally united with the tip ends of the blades spanned thereby.

The hereinbefore described procedure, which is particularly applicable in blading rotating elements, and the apparatus for carrying it out enable rotors and other elements to be accurately bladed with a minimum of time and skill and with the use of standard blade sections, thereby materially reducing manufacturing costs. Said procedure and apparatus are readily applicable to the blading of rotors and other elements having a peripheral portion shaped differently from that shown in Fig. 2, one such different shape being shown in Fig. 9 by way of illustration, and in addition, it should be understood that although a greater reduction in manufacturing cost can be effected by using standard forms of blades having single surfaced ends in connection with rotors or other elements having a plain or simple peripheral surface portion to which the blades are to be attached, it is not intended to limit the invention to the exact procedure and details of construction herein shown and described, as various modifications within the scope of the appended claims may occur to persons skilled in the art.

It is claimed and desired to secure by Letters Patent:

1. The method of blading rotors and other elements which comprises positioning and holding apertured and relative wide base and shroud ring forming strips in spaced concentric relation with their apertures alined for the insertion of blades therethrough, inserting blades through said alined apertures to provide an assembly in which the inner ends of the blades are approximately fiush with the inner side of the base strip, positioning and holding said assembly with the plain surface presented by the inner ends of the blades and by the portion of the inner side of the base strip included between the inner ends of the blades spaced in part from and forming with a peripheral portion of an element to be bladed having a width approximately equal to the width of the inner ends of the blades a first groove exposing a portion of the inner ends of said blades, substantially filling said first groove with weld metal and, welding the outer end of each blade to the outer contiguous portion of said shroud strip, forming a second oppositely facing groove exposing the remaining portion of said plain surface, substantially filling said second groove with weld metal, and removing opposite edge portions of both strips to provide a shroud structure approximately equal in width to the outer ends of said blades and a base structure approximately equal in width to the inner ends of said blades and to the peripheral portion of said element.

2. The method of blading rotors and other elements which comprises positioning and holding apertured and relative wide base and shroud ring forming strips in spaced concentric relation with their apertures alined for the insertion of blades therethrough, inserting blades through said alined apertures to provide an assembly in which the inner ends of the blades are approximately fiush with the inner side of said base strip, positioning and holding said assembly with the plain surface presented by the inner ends of the blades and by the portion of the inner side of the base strip included between the inner ends of the blades opposing a peripheral portion of an element to be bladed having a width approximately equal to the width of the inner ends of the blades in said assembly and having on one side thereof a projection coacting with the opposed portion of said plain surface to form a first groove, substantially filling said groove metal, welding the outer end of each stantially filling said second groove with weld metal, and removing opposite edge portions'of both strips to provide a shroud structure apouter ends of 6 bly including as parts thereof, blades supported by concentrically spaced, apertured base and shroud strips through which the blades extend with their inner ends terminating approximately flush with the inner side of the base strip, said shroud strip being considerably wider than the length of the blade receiving apertures therein and beingformed in segments disposed in endto-end abutting relation with intermediate portions of their ends spaced apart to provide a transversely extending slot between adjacent end apertures of abutting segments, said slot extending transversely beyond the ends of the apertures, and including an element having a periph separable from the other parts of said assembly merely by relative movement of said positioning means and the other parts of said assembly, and positioning in said assembly the apertured portion of said base strip opposing said peripheral portion of said element and the outer ends of the blades and proximate outer surface portions ROBERT C. ALLEN.

CECIL C. JORDAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,470,505 Steenstrup Oct. 9, 1923 1,547,838 steenstrup July 28, 1925 1,889,986 Haywood Dec, 5, 1933 1,932,278 Lacey Oct. 24, 1933 1,938,382 Haigh Dec. 5, 1933 2,080,563 Eskilson May 18, 1937 2,392,281 Allen Jan. 1, 1946 FOREIGN PATENTB Number Country Date 118,912 Austria Sept. 10, 1930 430,908 June 24. 1928 Germany 

